As the BBC launches a major new dinosaur series, Paul Upchurch says
their fossils hold clues to the future we face on Earth.

Tomorrow night, the BBC unveils its latest blockbuster series, Planet Dinosaur. Billed as the successor to 1999's Walking with Dinosaurs, it features creatures that are "bigger, badder and more bizarre than any you've seen before", from the monstrous Argentinosaurus, a 75-ton brute that roamed prehistoric South America, to "Predator X", the most powerful marine reptile in history, with a bite four times stronger than a Tyrannosaurus rex.

The series has prompted grumbling in some quarters that the BBC is simply flogging a dead horse (or reptile). Indeed, one of the most frequent questions people ask me when they learn that I am a palaeontologist specialising in dinosaur evolution is: "Haven't we already discovered everything there is to know?" Actually, there are still huge gaps in our knowledge – understandably, given that the creatures ruled the planet for roughly 160 million years. But recently, an impressive influx of new information has vastly increased our understanding of our predecessors as the rulers of the planet.

One of the key factors in this process has been an astonishing increase in the rate of discovery of new fossils. The first dinosaurs were recognised by scientists in the 1820s, resulting in classic names such as Megalosaurus and Iguanodon; the name for the entire group, Dinosauria ("terrible lizard"), was coined in 1842 by Sir Richard Owen, the creator of the Natural History Museum.

Since then, there has been a steady trickle of new discoveries, punctuated by occasional bursts, such as the "Bone Wars" of the 1870s and 1880s, when Edward Drinker Cope and Othniel Charles Marsh combed the western reaches of the United States in an effort to find, and name, the most new species. Yet the pace of discovery is now accelerating dramatically: it is estimated that we have discovered and named as many new species in the past 10-15 years as we did between 1820 and the late 1990s.

Many countries, including the UK, continue to unearth dinosaur fossils, some of which are new to science. However, the driving force behind recent discoveries are countries such as China, Brazil and Argentina.

These nations already possess some geological and climatic advantages. Extensive areas of desert or semi-arid land tend to expose fossil-bearing rocks at the surface. These areas can also contain valuable natural resources – so economically driven exploration results in the mapping of these rocks, and the reporting of any fossils that are ripe for collection. When we throw into the mix the national prestige associated with owning the "largest dinosaur" or the "earliest feathered dinosaur", plus the cash that museums and travelling exhibitions can make, it is easy to see why countries such as China have been eager to support palaeontological research.

To see the impact of such discoveries, just look at what we know about the origin of birds. Before 1990, palaeontologists were fairly convinced that modern birds had evolved from the bipedal meat-eating theropod dinosaurs (think Tyrannosaurus rex, Velociraptor and so on), but the only piece of evidence to fill the anatomical gap was the Archaeopteryx, with its dinosaur-like teeth, bony tail and bird-like wing feathers. Creationists were fond of pointing out these gaps and claiming that, if evolution had indeed happened, we palaeontologists should be able to provide the "missing links".

Well, over the past two decades, we have done exactly that: numerous small, feathered dinosaurs and early birds have been discovered, in China and elsewhere. These show how feathers first appeared as fine filaments that might have helped keep small dinosaurs warm, before evolving into larger structures that would have been useful for social displays and slowing the animal down as it "parachuted" out of trees. Eventually, these proto-feathers were transformed into flight feathers that appear indistinguishable from those of modern birds.

The tremendous influx of new information has not been driven merely by the discovery of more fossils. Our ability to glean information from what we find has also been transformed. Palaeobiological research has become a highly computerised and statistical science, which draws upon increased computing power, large databases and a wide array of analytical approaches. Fossil specimens can now be CT-scanned (the CT stands for "computed tomography"), modelled in 3-D in virtual environments to see how they looked and moved, probed for carbon and oxygen isotopes, assayed for various biological molecules, and examined using electron microscopes.

An excellent example is the impact of CT-scanning. Often, we come across specimens that cannot be studied with the naked eye, because they are obscured by rock that cannot be removed without risk to the fossil itself. There are also many small and delicate structures (such as the inner ear system) that cannot be easily studied, because they are surrounded by bone.

CT-scanning provides a non-destructive way of looking "inside" fossil specimens in order to extract new data. The size and shape of skeletal features can also be captured by CT-scanning or laser-scanning, and then converted into detailed and accurate 3-D models of the skull and skeleton inside our computers. These skeletons can then be made to walk or run in various ways, allowing palaeobiologists to test ideas about dinosaurs' locomotion and behaviour. These 3-D models can even determine the probable bite forces generated by dinosaurs, using an engineering technique known as Finite Element Analysis.

The impact of such techniques has been startling. Only last year, colleagues based in Bristol and Beijing announced that they had extracted information on the pigments in feathers of various theropods and early birds, providing data on the probable colouration and banding patterns of the feathers. Such work is likely to yield important insights into how and why feathers first evolved, and whether or not feathered dinosaurs used them for social signalling, such as attracting mates.

For the experts, studying the dinosaurs has never been more exciting. But this new era has important benefits for others, too. First, dinosaurs have always been the great ambassadors of science, inspiring many children with an interest in the natural world. Of course, few will grow up to be palaeontologists, but some will choose careers in other branches of science, and even those who do not are likely to be more scientifically literate in later life.

Second, dinosaurs are part of a rich fossil record that provides numerous opportunities to study how life and the Earth have evolved together. They were at their peak around 90 million years ago, a time characterised by high CO₂ levels, elevated global temperatures (perhaps as much as five or 10 degrees warmer than today), little ice cover at the poles, and limited seasonal variation in climate.

Dinosaurs therefore provide one of many strands of palaeontological and geological evidence that will help us understand how life responds to a warmer planet. Given the current predictions on global warming, it is surely worth studying how such events affected the organisms from which we inherited the planet.

Dr Paul Upchurch is Reader in Palaeobiology at University College London. 'Planet Dinosaur' starts tomorrow on BBC One at 8.30pm